In traditional, electrical devices such as a mother board and a power supply are arranged in a computer case. The electrical devices generate heat in operation, and multiple heat dissipation fans are commonly arranged in the computer case in order to ensure stability of the system. Generally, a fan supporter is arranged in the computer case and the heat dissipation fans are fixed to the fan supporter. The heat dissipation fans generate forced airflow and heat is thereby dissipated from the computer case.
In general, only a side of the fan mounted in the computer case is fixed with the fan supporter. A hot airflow blown from an air outlet of the fan is allowed to flow back to outside of an air inlet of the fan, because the air inlet of the fan is connected with the fan supporter and the air outlet is therefore hung. The air inlet is screwing connected with the fan supporter, and most of the back flowing hot air is blocked by the fan supporter and therefore cannot flow into the air inlet. However, a part of the hot air is re-sucked into the air inlet through a gap between the fan supporter and the fan. Accordingly, a heat dissipation performance of the fan is decreased by the back flowing hot air sucked thereinto. Increasing length of the fan to increase a distance between the air inlet and air outlet could reduce the back flowing hot air sucked thereinto. However, the hung end of the fan vibrates to impact adjacent portions of the computer case when in a high frequency rotation and noises therefore occur. The length of the fan is longer, the noises are more obvious.
In views of this, in order to solve the above disadvantage, the present inventor studied related technology and provided a reasonable and effective solution in the present disclosure.